I am not sure about this https://www.waffengebraucht.at/waffen/kugelrepetierer/carcano-8x57is--490252

its offered to be a 8x57IS

if true it could be a so called irish Mannlicher 1904 action https://www.gunboards.com/threads/steyr-1904-mannlicher-irish-mannlicher.45346/page-2

iirc, they were made from parts on stock to be sold with surplus M 88 rifles in 1904 when the 8x57I was still the official german military cartridge, also change for the M 88 clip.
could be that steyr sold this in austria were it was rebuild into a hunting rifle.